This invention relates to a supply system equipped with a lens design function, with which a spectacle lens with good appearance and optical performance can be obtained even when the difference in prescription, such as the diopter, between the left and right eyes is over a specific amount, and furthermore with which optical performance can be taken into account when the wearer changes his or her prescription and new spectacles are produced, or when the eyewear history of a customer is updated.
There are already known systems for the online ordering of spectacle lenses (see Japanese Patent No. 2,982,991, for instance). With this conventional system, a computer is set up on the side where the spectacle lenses are ordered, and a manufacturer-side computer is connected to this order-side computer so as to allow the exchange of information, with this computer executing order receipt processing such as obtaining lens design data on the basis of order information such as a lens prescription transmitted from the order-side computer. The order-side computer and the manufacturer-side computer perform computational processing according to specific input operations, and perform the processing necessary for placing and taking orders for spectacle lenses while exchanging information with each other.
In prescribing spectacle lenses that correct the vision of a patient""s eyes, lenses of the same refractive power (diopter) are prescribed when the left and right eyes both have the same visual acuity, so the curvature of the first refractive surface and the second refractive surface is also the same, and the optical performance, such as astigmatism, curvature of field, and distortion, is also the same. If the visual acuity of the left and right eyes is not the same, however, lenses having different refractive power (diopter) will of course be prescribed.
According to Tscherning""s ellipse, which Tscherning discovered as a geometric solution for eliminating astigmatism of a spectacle lens, the optimal base curve for eliminating astigmatism (the refractive power of the first refractive surface) varies. Consequently, if the visual acuity differs between the left and right eyes, the base curve of the left and right lenses must also be different according to Tscherning""s ellipse.
Therefore, when lenses are designed according to Tscherning""s ellipse, if there is a great difference in visual acuity between the left and right eyes as above, the left and right base curves will also be markedly different.
This means that the curved surface shape of the left and right spectacle lenses looks very unbalanced when the spectacles are viewed from the outside. Consequently, although optical performance is good, the appearance is quite poor.
Furthermore, since the curved surface shape is different for each individual lens on the lens manufacturer side, another disadvantage is higher manufacturing costs.
Accordingly, the same base curve is sometimes used within a specific diopter range in order to lower the manufacturing costs. However, lenses manufactured by this method may have a base curve that is not exactly optimal, so a problem is that the optical performance is inevitably inferior.
Naturally, if the base curves are merely made the same on the left and right in order to improve the appearance, optical performance will be markedly deteriorated in some cases. Thus, if emphasis is placed on the optical performance of the lenses, the cost will be higher and there will be cases in which appearance suffers. On the other hand, the problem with improving the appearance is that the optical performance may suffer.
Also, juvenile myopia tends to increase over time up to a certain age, and this is accompanied by changes in the prescription values for the spectacle lenses. Some wearers, however, are physiologically sensitive to changes in prescription values. That is, they experience severe discomfort when they wear lenses manufactured with a new prescription, and in some cases the body itself may be affected. These symptoms may appear even in regular customers, although not pronounced.
Research conducted by the inventors seems to indicate the primary cause of this to be as follows.
When a lens prescription changes, lenses having a curved surface shape and so forth that match this new prescription are newly designed and manufactured for supply to the customer. In this case, it is not uncommon for the newly designed and manufactured lenses that match the new prescription to have optical performance (astigmatism, curvature of field, and distortion) that is different from the optical performance of the old lenses designed to match the old prescription.
It is believed that symptoms such as discomfort will most often appear if this difference in optical performance goes beyond a certain level.
Thus, the difference in optical performance has been a serious problem, one that occurs due to a diopter difference in prescription lenses resulting from differences between the left and right eyes, or to a diopter difference between new and old lenses.
Unfortunately, the physician who gives the prescription and the business placing the order (such as an optician) do not have access to information about lens design, which has made it difficult to solve this problem.
Also, the existing spectacle lens supply systems mentioned above merely involved having the ordering side (such as an optician) specify lenses to a lens manufacturer, who then supplied the lenses, and no function was in place for solving the above-mentioned problem.
The present invention was conceived in light of the above situation, and it is an object thereof to provide a spectacle lens manufacturing method and a spectacle lens supply method with which good optical performance and good appearance can be both be achieved.
The first means for solving the above problem is a spectacle lens supply method, in which a computer is set up on a spectacle lens order side and a computer that is connected to this order-side computer such that information can be mutually exchanged is provided on the manufacturer side, and spectacle lenses are supplied by having the order-side computer and the manufacturer-side computer perform computations according to specific input operations and perform the processing required for the taking and/or placing of orders for spectacle lenses while exchanging information with each other,
characterized in that when spectacle lens information, spectacle frame information, prescription values, layout information, processing instructions information, and other such processing condition data required for processing is transmitted by the order-side computer to the manufacturer-side computer, a lens design program installed on the manufacturer-side computer performs optical lens design tailored to the customer on the basis of the transmitted data for lens information so that the optical performance of the left and right lenses will be similar, and the lenses are manufactured according to this design.
The second means is the spectacle lens supply method according to the first means, wherein the lens design program further performs optical lens design that approximates the left and right base curves to each other.
The third means is the spectacle lens supply method according to the first means, wherein the optical performance consists of at least one of astigmatism, curvature of field, and distortion.
The fourth means is the spectacle lens supply method according to the first means, comprising the steps of:
selecting the left and right lenses from a lens design table prepared on the basis of prescription values when the lens design program approximates the optical performance of the left and right eyes to each other;
comparing the convex surface base curve difference between the selected left and right lenses; and
when this base curve difference is over a predetermined standard, performing lens redesign in which the convex surface curve of one lens is made to have an aspherical shape similar to that of the convex surface curve of the other lens so that the astigmatism is substantially the same.
The fifth means is the spectacle lens supply method according to the second means, wherein the optical lens design is such that the difference in convex surface base curves of the left and right spectacle lenses is no more than 1 D.
The sixth means is the spectacle lens supply method according to the second means, wherein a display means for comparing data including the lens shape before the curve matching and the prescription data for this lens, to data including the lens shape after the curve matching and the prescription data for this lens, is transferred to and displayed at the computer set up on the side where spectacle lens is ordered.
The seventh means is a spectacle lens supply system, comprising a computer set up on a spectacle lens order side and a manufacturer-side computer that is information exchangeably connected to this order-side computer and has a customer database including spectacle lens prescription date and lens design data,
in which the order-side computer and the manufacturer-side computer perform computations according to specific input operations and perform the processing required for the taking and/or placing of orders for spectacle lenses while exchanging information with each other,
wherein the manufacturer-side computer has the function of performing lens design such that a customer will experience substantially no discomfort originating in an optical performance difference when changing from old to new lenses, by selecting or producing new design data for a lens on the basis of customer spectacle lens processing condition data required for processing, such as spectacle lens information, spectacle frame information, prescription values, layout information, and processing instructions information, when this data is transmitted from the order-side computer to the manufacturer-side computer, and making the optical performance of the new lenses produced with this new design data approximate the optical performance of the old lenses produced with the old design data based on the old prescription values of the pre-registered customer database.
The eighth means is a spectacle lens supply system, comprising a computer set up on a spectacle lens order side and a manufacturer-side computer that is information exchangeably connected to this order-side computer and has a customer database including spectacle lens prescription data and lens design data,
in which the order-side computer and the manufacturer-side computer perform computations according to specific input operations and perform the processing required for the taking and placing of orders for spectacle lenses while exchanging information with each other,
wherein, when customer spectacle lens processing condition data required for processing, such as spectacle lens information, spectacle frame information, prescription values, layout information, and processing instructions information, is transmitted from the order-side computer to the manufacturer-side computer, the manufacturer-side computer has the function of performing processing comprising:
a step of checking whether there is any old prescription data for that customer;
a step of selecting or producing lens design data matching the new prescription values as lens design data for the new prescription values if no old data for that customer exists in the manufacturer-side computer, and setting this data as the design data for producing the new lenses;
an optical performance comparison step in which, if there is old prescription data for the customer, the new lens design data for the new prescription values is selected or produced, and the optical performance of the new lenses designed on the basis of the newly selected or produced new design data is compared to the optical performance of the old lenses designed with the old design data matching the old prescription values; and
a step in which, when the results of comparing the optical performance as above indicate that the optical performance difference is within a range such that the customer will experience substantially no discomfort originating in an optical performance difference when changing from old to new lenses, the selected or produced new design data is set as the design data for producing the new lenses, and when said difference goes outside a range in which the customer will experience substantially no discomfort originating in an optical performance difference when changing from old to new lenses, new design data is newly selected or produced for putting the optical performance difference within said range before returning to said optical performance comparison step and such processing is repeated until the optical performance difference is within said range.
The ninth means is the spectacle lens supply system according to the seventh or eighth means, wherein the newly determined new design data is registered for the first time or updated in the customer database.
The tenth means is the spectacle lens supply system according to the seventh or eighth means, wherein, when there is old prescription data for the customer, a step is provided for comparing the difference between the old and new prescription values, and if this difference is not over 0.5 D as the diopter difference, the new lens design data for the new prescription values is selected or produced without performing the optical performance comparison step, and this data is set as the design data for producing the new lenses.
The eleventh means is the spectacle lens supply system according to the seventh or eighth means, wherein the lens design data is such that the difference in the curve of a first refractive surface of the left and right spectacle lenses is no more than 1 D.
The twelfth means is the spectacle lens supply system according to the seventh or eighth means, wherein the optical performance is at least one of astigmatism, curvature of field, and distortion.
The thirteenth means is the spectacle lens supply system according to the seventh or eighth means, wherein the curvature of at least one of the first refractive surfaces of the left and right spectacle lenses is selected such that this curved surface will be aspherical.
The fourteenth means is a method for manufacturing a spectacle lens, involving the design and manufacture of left and right spectacle lenses that make up a pair of spectacles in which the prescription including diopter is different for the left and right eyes,
wherein, if there is more than a specific amount of difference in the prescription including diopter between the left and right eyes:
when the refractive surfaces in front of the left and right spectacle lenses are termed the first refractive surfaces and the refractive surfaces on the eye side are termed the second refractive surfaces, in designing the curvature of the curved surfaces of the first and second refractive surfaces of the left and right spectacle lenses, the curvature of the first and second refractive surfaces of at least one of the left and right spectacle lenses is selected so that the left and right spectacle lenses satisfy their respective prescription conditions including the diopter so that the difference in the curvature of the first refractive surfaces between the left and right spectacle lenses falls within a specific range.
The fifteenth means is a method for manufacturing a spectacle lens, involving the design and manufacture of left and right spectacle lenses that make up a pair of spectacles in which the prescription including diopter is different for the left and right eyes,
wherein, if there is more than a specific amount of difference in the prescription including diopter between the left and right eyes:
when the refractive surfaces in front of the left and right spectacle lenses are termed the first refractive surfaces and the refractive surfaces on the eye side are termed the second refractive surfaces, in designing the curvature of the curved surfaces of the first and second refractive surfaces of the left and right spectacle lenses, the curvature of the first and second refractive surfaces of at least one of the left and right spectacle lenses is selected so that the left and right spectacle lenses satisfy their respective prescription conditions including the diopter, so that the optical performance of each lens falls within an acceptable range, and so that the difference in the curvature of the first refractive surfaces between the left and right spectacle lenses falls within a specific range.
The sixteenth means is the method for manufacturing a spectacle lens pertaining to the fourteenth or fifteenth means, wherein the difference in the diopter between the left and right eyes is at least 0.5 D when the diopter prescription out of said prescription including the diopter includes a positive diopter, the difference in the diopter between the left and right eyes is at least 1 D when the diopter prescription includes a negative diopter, and the difference in the curvature of the first refractive surfaces of the left and right spectacle lenses is no more than 1 D.
The seventeenth means is the method for manufacturing a spectacle lens pertaining to the fifteenth means, wherein the optical performance consists of one or more of astigmatism, curvature of field, and distortion.
The eighteenth means is the method for manufacturing a spectacle lens pertaining to the fifteenth means, wherein the curvature of one or both of the first refractive surfaces of the left and right spectacle lenses is selected such that this curved surface will be aspherical.